The present invention relates to systems and methods for partial backout of application updates. More particularly, the present invention relates to resource integrity during partial backout of application updates.
Applications that run for long periods of time may fail before completing all desired processing. Applications use system software to update numerous recoverable resources and write associated recovery log records to document the updates that have been performed on the resources. The log records are stored within application log queues. For applications that have run for extended periods of time, many log records may have been generated and stored within the log queues at a time of failure of an application.
When an application failure or an application hosting system failure occurs, the log records are available within the log queues to reconstruct application states at the time of failure. The hosting system has the responsibility of performing recovery operations (e.g., rollback, backout) related to the failed application. Backout refers to a process of processing log records to identify application processing sequences and performing the represented operations to recover the resources.
However, the log records may be stored on different log media, including disks and tapes. Traversing this media is time consuming. Accordingly, for applications that have run for extended periods of time, processing the log records to reconstruct the state of the recoverable resources may take days or weeks to reconstruct the state of these resources.